diff --git a/src/PIM/Transforms/PimBufferizationPass.cpp b/src/PIM/Transforms/PimBufferizationPass.cpp
index 18d3522..eb3496b 100644
--- a/src/PIM/Transforms/PimBufferizationPass.cpp
+++ b/src/PIM/Transforms/PimBufferizationPass.cpp
@@ -63,7 +63,7 @@ void PimBufferizationPass::runOnOperation() {
 void PimBufferizationPass::annotateWeightsMemrefs(ModuleOp moduleOp, func::FuncOp funcOp) const {
   MLIRContext* ctx = funcOp.getContext();
   funcOp.walk([&](memref::GetGlobalOp getGlobalOp) {
-    bool isAlwaysWeight = llvm::all_of(getGlobalOp->getUsers(), [](auto user) -> bool { return isa<PimCoreOp>(user); });
+    bool isAlwaysWeight = llvm::all_of(getGlobalOp->getUsers(), [](auto user) -> bool { return isa<PimCoreOp>(user); }) && !getGlobalOp->getUsers().empty() ;
     if (isAlwaysWeight) {
       auto globalMemrefOp = moduleOp.lookupSymbol<memref::GlobalOp>(getGlobalOp.getName());
       assert("Weights must be constants" && globalMemrefOp.getConstant());